CN117043261A

CN117043261A - Fluoropolymer compositions

Info

Publication number: CN117043261A
Application number: CN202280019911.1A
Authority: CN
Inventors: A-C·勒古鲁什; M·科拉登; J·A·阿布斯莱姆
Original assignee: Solvay Specialty Polymers Italy SpA
Current assignee: Solvay Specialty Polymers Italy SpA
Priority date: 2021-03-10
Filing date: 2022-03-03
Publication date: 2023-11-10
Also published as: WO2022189266A1; US20240182695A1; JP2024509568A; EP4305103A1; KR20230154876A; BR112023016771A2

Abstract

The present application relates to a polymer composition comprising a polymer component a, a polymer component B and a polymer component C, the polymer component a consisting of one or more vinylidene fluoride (VDF) homopolymers in an amount of 90% -100% by weight of the polymer component a and optionally one or more VDF copolymers present in an amount of 0% -10% by weight of the polymer component a, the polymer component B consisting of one or more (per) fluoropolyethers in an amount of from 0.05% to 2% by weight based on the weight of the polymer component a and the polymer component C consisting of one or more per (halo) fluoropolymers in an amount of from 0.1% to 10% by weight based on the weight of the polymer component a. The composition is easy to process and has extremely high mechanical properties at elevated temperatures.

Description

Fluoropolymer compositions

Technical Field

The present application claims priority from European patent application No. 21161877.2 filed on EPO at day 3 and 10 of 2021. The entire contents of this application are incorporated herein by reference for all purposes.

The present application relates to thermoplastic fluoropolymer compositions based on vinylidene fluoride (1, 1 vinylidene fluoride, denoted "VDF" in the present application); to a process for making the thermoplastic fluoropolymer composition; and to articles comprising the fluoropolymer compositions of the present application.

The compositions of the present invention have high mechanical resistance, especially at high temperatures, and at the same time can be molded and extruded to form articles free of surface marks or cracks.

Background

Fluorocarbon resins, particularly vinylidene fluoride resins, have excellent mechanical properties over a wide temperature range, and are well-tolerated by high temperatures, organic solvents, and various chemically aggressive environments. Because of their nature, they are commonly used for the manufacture of articles by extrusion or injection molding, for example for the production of pipes, tubes, fittings, films, coatings, cable jackets, flexible pipes, etc.

To further improve the mechanical properties of these polymers, it is known to increase their molecular weight. This enables the use of these materials in very demanding applications, like for example marine pipelines, which require excellent properties in terms of impact resistance, high deformability (for unwind-winding), high heat resistance. Thus, while fluoropolymers having high molar masses (and thus high melt viscosities) are preferred for improved mechanical properties, processing these materials in the molten state is more difficult. In particular, they present rheological problems during extrusion and moulding, leading to an increase in the energy consumption during extrusion and more severe extrusion conditions to be applied (with a consequent risk of thermal degradation of the polymer). As known to those skilled in the art, higher molecular weight polymers will generally have higher viscosity in the molten state. When such high viscosity melts produce finished parts (by extrusion or injection molding), surface defects like cracks, shark skinning, fish eyes, etc. may form.

The present invention therefore aims to provide a fluoropolymer composition that combines a relatively low melt viscosity (thus yielding a finished part with high mechanical properties, excellent surface appearance) and extremely high mechanical resistance, especially at high temperatures.

WO 2007006645 A1 and WO 2007006646 A1 from the sorv specialty polymers company (Solvay Specialty Polymers) describe polymer compositions comprising a mixture of VDF-based homopolymers and copolymers, wherein the copolymers are at least 25% combined with processing additives, including (per) fluoropolyethers and per (halo) fluoropolymers. The compositions described in these documents have good mechanical properties and can be easily processed in order to obtain finished parts free of structural and surface defects.

However, there is a need for materials that, while maintaining the desired properties of the above materials, also impart further improved mechanical properties at high temperatures (e.g., temperatures above 130 ℃).

Disclosure of Invention

The present invention relates to a thermoplastic polymer composition comprising:

a) A vinylidene fluoride (VDF) -based polymer component A,

b) A polymer component B consisting of one or more (per) fluoropolyethers in an amount of from 0.05 to 2% by weight based on the weight of the polymer component A,

c) A polymer component C consisting of one or more per (halo) fluoropolymers in an amount of from 0.1% to 10% by weight based on the weight of polymer component A,

the composition is characterized in that the polymer component a consists of one or more vinylidene fluoride (VDF) homopolymers in an amount of 90-100% by weight of the polymer component a and optionally one or more VDF copolymers present in an amount of 0-10% by weight of the polymer component a, said one or more VDF copolymers, when present, comprising 80-99% by moles of recurring units derived from VDF and 1-20% by moles of comonomer recurring units derived from a different VDF.

Detailed Description

As stated above, the present invention relates to a thermoplastic polymer composition comprising three polymer components A, B and C.

Polymer component AIs a VDF-based polymer component consisting of one or more VDF homopolymers in an amount of from 90% to 100%, preferably from 95% to 100% by weight based on the total weight of polymer component a, and optionally one or more VDF copolymers in an amount of 0% to 10%, preferably 0% to 5% by weight based on the total weight of polymer component a, wherein optionally the one or more VDF copolymers (if present) comprise 80% to 99% by mole of recurring units derived from VDF and 1% to 20% by mole of recurring units derived from a comonomer other than VDF.

In other words, the polymer component a may consist of one or more VDF homopolymers or a mixture of one or more VDF homopolymers and one or more VDF copolymers as defined above, wherein the VDF copolymer comprises 10% or less, preferably 5% or less by weight based on the total weight of the polymer component a.

The term "homopolymer" of VDF refers to polymers in which substantially all of the repeat units are derived from VDF. As the skilled person will appreciate, the VDF homopolymer may also contain very small amounts of repeat units other than VDF. The repeating units other than VDF may be derived from monomeric impurities or from free radical initiators used during polymerization or from chain ends of chain transfer agents, but these do not substantially affect the properties of the polymer. For the purposes of the present invention, a VDF polymer is defined as a VDF homopolymer if it contains less than 1% mol of recurring units other than VDF.

For the purposes of the present invention, it is preferred that polymer component A consists only of one or more VDF homopolymers, however, as mentioned above, polymer component A may also comprise up to 10%, preferably up to 5% by weight of one or more VDF copolymers, based on the total weight of polymer component A.

VDF copolymers suitable for the present invention comprise 80% to 99% by moles of recurring units derived from VDF and 1% to 20% by moles of recurring units derived from one or more comonomers other than VDF.

The choice of comonomer for the VDF copolymer used in the present invention is not particularly limited and any hydrogenated, partially fluorinated or fully fluorinated comonomer may be used.

The comonomer other than VDF is preferably selected from fluorinated comonomers and more preferably from vinyl fluoride (VF 1), chlorotrifluoroethylene (CTFE), hexafluoropropylene (HFP), tetrafluoroethylene (TFE), trifluoroethylene (TrFE), perfluoroalkyl vinyl ethers (in these, having the formula cf2=cfo-CF ₃ Of these, perfluoromethyl vinyl ether is preferred), perfluoroalkyl ethylene (of which perfluorobutyl ethylene is preferred), (perfluorodioxole (as described in U.S. patent No. 5,597,880), or mixtures thereof.

The Melt Flow Index (MFI) of the polymer component A is preferably chosen to be less than 20, preferably less than 10, more preferably less than 8g/10min, even more preferably less than 7g/10min, most preferably less than 5g/10min, and at least 0.01, preferably at least 0.05, more preferably at least 0.1g/10min. (measured at 230 ℃ C. Under a piston load of 21.6kg according to ASTM D-1238 standard).

Polymer component BConsists of one or more (per) fluoropolyethers. In the context of the present invention, the term (per) fluoropolyether is intended to mean a polymer comprising recurring units (R1) comprising at least one ether linkage in the main chain and at least one fluorine atom (fluoropolyoxyalkylene chain).

Preferably, the recurring units R1 of the (per) fluoropolyether are selected from the group consisting of:

(I) -CFX-O-, wherein X is-F or-CF ₃ ；

(II)-CF ₂ -CFX-O-, wherein X is-F or-CF ₃ ；

(III)-CF ₂ -CF ₂ -CF ₂ -O-；

(IV)-CF ₂ -CF ₂ -CF ₂ -CF ₂ -O-；

(V)-(CF ₂ ) _j -CFZ-O-, wherein j is an integer selected from 0 and 1, and Z is a fluoropolyoxyalkylene chain comprising from 1 to 10 repeating units selected from the above classes (I) to (IV);

and mixtures thereof.

If the (per) fluoropolyethers comprise recurring units R1 of different types, it is advantageous if said recurring units are randomly distributed along the fluoropolyoxyalkylene chain.

Preferably, the (per) fluoropolyether polymer component B comprises and preferably consists of a compound according to formula (I) herein below:

T ₁ -(CFX) _p -O-R _f -(CFX) _p’ -T ₂ (I)

wherein:

-each X is independently F or CF ₃ ；

-p and p', equal to or different from each other, are integers from 0 to 3;

-R _f is a fluoropolyoxyalkylene chain comprising repeating units selected from the group consisting of:

(i) -CFXO-, wherein X is F or CF ₃ ，

(ii)-CF ₂ CFXO-wherein X is F or CF ₃ ，

(iii)-CF ₂ CF ₂ CF ₂ O-，

(iv)-CF ₂ CF ₂ CF ₂ CF ₂ O-，

(v)-(CF ₂ ) _j -CFZ-O-, wherein j is an integer selected from 0 and 1, and Z is a compound having the formula-OR _f ’T ₃ Wherein, the group of the (C) is,

-R _f ' is a fluoropolyoxyalkylene chain comprising from 0 to 10 repeating units selected from the group consisting of:

-CFXO-、-CF ₂ CFXO-、-CF ₂ CF ₂ CF ₂ O-、-CF ₂ CF ₂ CF ₂ CF ₂ O-,

wherein each X is independently F or CF ₃ The method comprises the steps of carrying out a first treatment on the surface of the And T is ₃ Is C ₁ -C ₃ Perfluoroalkyl groups and mixtures thereof;

-T ₁ and T ₂ Independently selected from

i)H，

ii) a halogen atom, and (ii) a halogen atom,

iii)C ₁ -C ₃₀ a terminal group optionally comprising a heteroatom selected from O, S, N and/or halogen atoms.

Preferably T ₁ And T ₂ Selected from the group consisting of:

(j) -Y ', wherein Y' is selected from-H, halogen such as-F, -Cl, C ₁ -C ₃ Perhaloalkyl radicals such as-CF ₃ 、-C ₂ F ₅ 、-CF ₂ Cl、-CF ₂ CF ₂ Chain ends of Cl;

(jj)-E _r -A _q -Y” _k wherein k, r and q are integers and q=0 or 1, r=0 or 1 and k is between 1 and 4, preferably between 1 and 2, E represents a functional linking group comprising at least one heteroatom selected from O, S, N; a represents C ₁ -C ₂₀ A divalent linking group; and Y' represents a functional end group.

The functional group E may comprise amide, ester, carboxylic acid, thiocarboxylic acid, ether, heteroaromatic, thioether, amine and/or imine groups.

Non-limiting examples of functional linking groups E are notably-CONR- (r=h, C) ₁ -C ₁₅ Substituted or unsubstituted straight-chain or cyclic aliphatic radical, C ₁ -C ₁₅ A substituted or unsubstituted aromatic group); -COO-; -COS-; -CO-; heteroatoms (e.g., -O-, -S-); -NR' - (r=h, C ₁ -C ₁₅ Substituted or unsubstituted straight-chain or cyclic aliphatic radical, C ₁ -C ₁₅ A substituted or unsubstituted aromatic group); 5-or 6-membered aromatic heterocycles containing one or more hetero atoms selected from N, O, S, identical to or different from each other, in particular triazines, e.g.

Divalent C ₁ -C ₂₀ The linking group a is preferably selected from the following classes:

1) Straight-chain substituted or unsubstituted C ₁ -C ₂₀ An alkylene chain, optionally containing heteroatoms in the alkylene chain; preferably a linear aliphatic group comprising a compound having the formula- (CH) ₂ ) _m -a moiety wherein m is an integer between 1 and 20, and which optionally comprises amide, ester, ether, thioether, imine groups and mixtures thereof;

2) (alkylene) alicyclic C ₁ -C ₂₀ Radicals or (alkylene) aromatic C ₁ -C ₂₀ A group optionally containing heteroatoms in the alkylene chain or in the ring, and optionally containing amide, ester, ether, sulfide, imine groups, and mixtures thereof;

3) Linear or branched polyalkoxyl chain comprising in particular recurring units selected from: -CH ₂ CH ₂ O-、-CH ₂ CH(CH ₃ )O-、-(CH ₂ ) ₃ O-、-(CH ₂ ) ₄ O-, which optionally comprises amide, ester, ether, thioether, imine groups, and mixtures thereof.

Examples of suitable functional groups Y ' are notably-OH-SH, -OR ', -SR ', -NH ₂ 、-NHR’、-NR’ ₂ 、-COOH、-SiR’ _d Q _3-d 、-CN、-NCO、1, 2-and 1, 3-diols or as cyclic acetals and ketals (e.g., dioxolane or dioxane), COR', -CH (OCH) ₃ ) ₂ 、-CH(OH)CH ₂ OH、-CH(COOH) ₂ 、-CH(COOR’) ₂ 、-CH(CH ₂ OH) ₂ 、-CH(CH ₂ NH ₂ ) ₂ 、-PO(OH) ₂ 、-CH(CN) ₂ Wherein R ' is an alkyl group, an alicyclic OR aromatic, substituted OR unsubstituted group optionally containing one OR more fluorine atoms, Q is OR ', R ' has the meaning ofD is an integer between 0 and 3.

One or more functional end groups Y' may be attached to groups A and/or E: for example, when A is an (alkylene) aromatic C ₁ -C ₂₀ When groups are present, it is possible that two or more Y' groups are attached to the aromatic ring of group A.

More preferably, the (per) fluoropolyethers of the present invention conform to formula (I) above herein, wherein T ₁ And T ₂ Selected from the group consisting of: -H; halogen such as-F and-Cl; c (C) ₁ -C ₃ Perhaloalkyl radicals such as-CF ₃ 、-C ₂ F ₅ 、-CF ₂ Cl、-CF ₂ CF ₂ Cl；-CH ₂ OH；-CH ₂ (OCH ₂ CH ₂ ) _n OH (n is an integer between 1 and 3); -C (O) OH; -C (O) OCH ₃ ；-CONH-R _H- OSi(OC ₂ H ₅ ) ₃ (wherein R is _H Is C ₁ -C ₁₀ An alkyl group); -CONHC ₁₈ H ₃₇ ；-CH ₂ OCH ₂ CH(OH)CH ₂ OH；-CH ₂ O(CH ₂ CH ₂ O) _n* PO(OH) ₂ (wherein n ^* Between 1 and 3);

and mixtures thereof.

Most preferably, the (per) fluoropolyether polymer component B comprises and preferably consists of a compound selected from the group consisting of:

(a)HO-CH ₂ CF ₂ O(CF ₂ O) _n’ (CF ₂ CF ₂ O) _m’ CF ₂ CH ₂ -OH, m 'and n' are integers, wherein the ratio m '/n' is generally between 0.1 and 10, preferably between 0.2 and 5;

(b)HO(CH ₂ CH ₂ O) _n CH ₂ CF ₂ O(CF ₂ O) _n’ (CF ₂ CF ₂ O) _m’ CF ₂ CH ₂ (OCH ₂ CH ₂ ) _n OH, m 'and n' are integers, wherein the ratio m '/n' is in the range between 0.1 and 10, preferably between 0.2 and 5, and n is in the range between 1 and 3;

(c)HCF ₂ O(CF ₂ O) _n’ (CF ₂ CF ₂ O) _m’ CF ₂ h, m 'and n' are integers, wherein the ratio m '/n' is in the range between 0.1 and 10, preferably between 0.2 and 5;

(d)FCF ₂ O(CF ₂ O) _n’ (CF ₂ CF ₂ O) _m’ CF ₂ f, m 'and n' are integers, wherein the ratio m '/n' is in the range between 0.1 and 10, preferably between 0.2 and 5.

According to a preferred embodiment of the invention, the thermoplastic fluoropolymer composition comprises a (per) fluoropolyether selected from the types (a) and (b) above. The presence of terminal hydroxyl groups has been found to be particularly beneficial for the processability of the compositions of the present invention.

The weight average molecular weight of the (per) fluoropolyether is preferably comprised between 400 and 100000, more preferably between 600 and 20000.

The (per) fluoropolyethers of the present invention may notably be produced by photo-induced oxidative polymerization (photo-oxidation reaction) of per (halo) fluoromonomers, as described in U.S. patent No. 3,665,041. Typically, the (per) fluoropolyether structure may be prepared by reacting at a low temperature, typically below-40 ℃, at a temperature of less thanIs obtained by combining hexafluoropropylene and/or tetrafluoroethylene with oxygen under u.v. irradiation of the wavelength of (a). The subsequent conversion of the end groups as described in U.S. Pat. nos. 3,847,978 and 3,810,874 is notably carried out on the crude product from the photooxidation reaction.

The (per) fluoropolyethers of the types (a), (b), (c) and (d) described above are notable from the company Solvay Solexis s.p.a.) of the sor visulaxZDOL、ZDOL TX、And->Z or->M is available.

The amount of polymer component B in the thermoplastic polymer composition of the present invention is from 0.05% to 2%, preferably from 0.06% to 1.5%, more preferably from 0.07% to 1%, most preferably from 0.1% to 0.8% by weight based on the weight of polymer component a.

Polymer component CConsists of one or more per (halo) fluoropolymers. For the purposes of the present invention, the term "per (halo) fluoropolymer" is intended to mean a fluoropolymer substantially free of hydrogen atoms. The per (halo) fluoropolymer may further comprise one or more other halogen atoms (Cl, br, I).

The term "substantially free of hydrogen atoms" is understood to mean that the per (halo) fluoropolymer is prepared from ethylenically unsaturated monomers (per (halo) fluoromonomers) containing at least one fluorine atom and free of hydrogen atoms. As the skilled person will appreciate, the per (halo) fluoropolymers may also contain very small amounts of recurring units containing hydrogen atoms, which may be derived from monomeric impurities, or from free radical initiators used during polymerization or from chain ends of chain transfer agents, but which do not substantially affect the properties of the polymer.

The per (halo) fluoropolymer may be a homopolymer of per (halo) fluoromonomer or a copolymer comprising repeat units derived from more than one per (halo) fluoromonomer.

Non-limiting examples of suitable per (halo) fluoromonomers are notably:

-C ₂ -C ₈ perfluoroolefins, e.g. tetrafluoroethylene and hexafluoroPropylene;

-chloro-and/or bromo-and/or iodo-C ₂ -C ₆ Fluoroolefins such as chlorotrifluoroethylene;

-conform to the general formula CF ₂ ＝CFOR _f3 (halo) fluoroalkyl vinyl ethers, wherein R _f3 Is C ₁ -C ₆ Per (halo) fluoroalkyl, e.g. -CF ₃ 、-C ₂ F ₅ 、-C ₃ F ₇ ；

-CF ₂ ＝CFOX ₀₁ Per (halo) fluoro-oxyalkyl vinyl ether, wherein X ₀₁ Is C having one or more ether groups ₁ -C ₁₂ Per (halo) fluorooxyalkyl, like perfluoro-2-propoxy-propyl;

-conform to the general formula CF ₂ ＝CFOCF ₂ OR _f4 (halo) fluoroalkyl vinyl ethers, wherein R _f4 Is C ₁ -C ₆ Or per (halo) fluoroalkyl, e.g. -CF ₃ 、-C ₂ F ₅ 、-C ₃ F ₇ Or C having one or more ether groups ₁ -C ₆ Per (halo) fluorooxyalkyl, -C ₂ F ₅ -O-CF ₃ ；

Conforming CF ₂ ＝CFOY ₀₁ Functional per (halo) fluoro-oxyalkyl vinyl ether of (A), wherein Y ₀₁ Is C ₁ -C ₁₂ Per (halo) fluoroalkyl, or C with one or more ether groups ₁ -C ₁₂ Per (halo) fluorooxyalkyl, and Y ₀₁ Comprising carboxylic or sulphonic acid groups in the form of their acids, acid halides or salts;

-per (halo) fluorodioxoles.

Suitable examples of per (halo) fluoropolymers for use in the composition according to the invention are notably TFE copolymers and CTFE copolymers.

Preferred per (halo) fluoropolymers are notably TFE copolymers.

In a preferred embodiment, said polymer component C comprises and preferably consists of one or more per (halo) fluoropolymers selected from TFE copolymers comprising at least 2% wt, preferably at least 7% wt, and at most 30% wt, preferably at most 20% wt, more preferably at most 13% wt, of recurring units derived from at least one fluorinated comonomer selected from the group consisting of:

(i) Conforming CF ₂ ＝CFOR _f1’ Wherein R is _f1’ Is C ₁ -C ₆ Perfluoroalkyl groups, e.g. CF ₃ 、C ₂ F ₅ 、C ₃ F ₇ The method comprises the steps of carrying out a first treatment on the surface of the And/or

(ii) Conforming CF ₂ ＝CFOX ₀ Perfluoro-oxyalkyl vinyl ether of (1), wherein X ₀ Is C having one or more ether groups ₁ -C ₁₂ Perfluorooxyalkyl groups such as perfluoro-2-propoxy-propyl; and/or

(iii)C ₃ -C ₈ Perfluoroolefins such as hexafluoropropylene.

Suitable TFE copolymers are, for example, TFE/PAVE polymers. These polymers are known in the industry as PFA and MFA polymers and are commercially available (e.g., by Solvin specialty polymers Inc. under the trade nameCommercialization). Such polymers can be made using known polymerization techniques described in the literature. Reference is made to, for example, european patent EP 633274 B1 and PCT application WO 2016096961 from the Sorve specialty Polymer company.

In general, the polymers used as polymer component C in the present invention can be prepared in an aqueous polymerization medium in a pressurized reactor using emulsion and/or suspension polymerization techniques, monomers being fed to this reactor and polymerization initiated using a free radical initiator. Surfactants such as fluorinated and/or non-fluorinated surfactants may be used during polymerization to help stabilize the emulsion. Conventional chain transfer agents may also be used to control the molecular weight and viscosity of the polymer.

Typically, the preparation of the polymers suitable for use in the present invention is carried out in emulsion and the resulting material is a polymer finely dispersed in aqueous medium in the form of a latex. For subsequent processing, the polymer is extracted from the latex using known techniques, such as, for example, by freeze coagulation. The extracted polymer is washed with demineralised water and dried at high temperature (e.g. 150.160 ℃) to remove residual moisture.

Good results have been obtained with TFE copolymers in which the fluorinated comonomer is C as specified above ₃ -C ₈ Perfluoroolefins and/or perfluoroalkyl vinyl ethers; particularly good results have been achieved with TFE copolymers wherein the fluorinated comonomer is hexafluoropropylene and/or perfluoromethyl vinyl ether (PMVE) (having the formula CF ₂ ＝CFOCF ₃ )。

When the per (halo) fluoropolymer is a TFE copolymer wherein the fluorinated comonomer is a perfluoroalkyl vinyl ether as specified above, the TFE copolymer is present at 1s ^-1 Advantageously has a dynamic viscosity of at most 100Pa×sec, preferably at most 50Pa×sec, more preferably at most 30Pa×sec, most preferably at most 10Pa×sec at a temperature of 280 ℃.

Dynamic viscosity is typically measured using a parallel plate clamp with a controlled strain rheometer, using an actuator to apply a deforming strain to the sample and using a separate sensor to measure the resultant stress generated within the sample.

According to an embodiment of the present invention, the per (halo) fluoropolymer of the present invention is selected from tetrafluoroethylene/perfluoromethyl vinyl ether (TFE/PMVE) copolymers consisting essentially of:

-from 4% to 25% mole, preferably from 5% to 20% wt, most preferably from 10% to 16% mole of recurring units derived from PMVE; and

from 96% to 75% by moles, preferably from 95% to 80% by moles, most preferably from 90% to 84% by moles of recurring units derived from TFE.

Preferably, the polymer component C is melt processable.

For the purposes of the present invention, the term "melt-processible" means that the polymer component C can be processed (i.e.made into shaped articles such as films, fibers, tubes, wire coatings, etc.) by conventional melt extrusion, injection or casting methods. When using a parallel plate clamp with a controlled strain rheometer, the deformation strain is applied to the sample using an actuator and the resultant stress generated within the sample is measured using a separate sensor At 1s ^-1 At a shear rate of about 30 ℃ above the melting point, preferably at T _m2 At temperatures of + (30.+ -. 2 ℃ C.), it is typically required to have a temperature of less than 10 ⁶ Dynamic viscosity of pa×s.

Melting Point (in T) _m2 Meter) is determined by DSC at a heating rate of 10 ℃/min according to ASTM D3418.

When the polymer component C is melt-processible, it is at 1s ^-1 Preferably has a dynamic viscosity of less than 2000Pa x s, more preferably less than 700Pa x s, under the conditions specified above.

If the polymer component C is melt-processible, the ratio between the melt flow index of the polymer component C and the melt flow index of the polymer component A is advantageously at least 5, preferably at least 10, more preferably at least 20.

The melt flow index of polymer component C was measured according to ASTM test number 1238.

The amount of polymer component C in the thermoplastic polymer composition of the present invention is from 0.1% to 10%, preferably from 0.2% to 8%, more preferably from 0.3% to 5%, most preferably from 0.5% to 4% by weight of polymer component a.

End chains, impurities, defects and small amounts of other comonomers may be present in the polymer components A, B and C, but these do not substantially affect the properties of the polymer components.

The composition of the present invention may optionally comprisePlasticizer(s). Plasticizers suitable for the compositions of the present invention may be selected from the usual monomeric or polymeric plasticizers for fluoropolymers.

Plasticizers described in US 3541039 (PENNWALT CORP), and those described in US 4584215 (french Ai Dier petroleum institute (INST FRANCAIS DU PETROL)) are suitable for the compositions of the present invention.

The incorporation of plasticizers into the compositions of the invention defined above without difficulty results in compositions whose impact strength, in particular at low temperatures, is advantageously improved. In other words, plasticizers can be advantageously used in the compositions of the present invention to improve the low temperature behavior of the final parts made from the compositions of the present invention, especially when these parts are subjected to extreme operating temperatures.

Among the monomeric plasticizers, mention may be made notably of dibutyl sebacate (DBS), N-butyl sulfonamide, tri-N-butyl acetyl citrate having the formula:

dibutoxyethyl adipate having the formula:

a plasticizer that has been shown to be particularly advantageous in the context of the present invention is DBS:

(C ₄ H ₉ -OOC-(CH ₂ ) ₈ -COO-C ₄ H ₉ )。

among the polymeric plasticizers, mention may notably be made of polymeric polyesters, such as those derived from adipic acid, azelaic acid or sebacic acid and diols, and mixtures thereof, provided that their molecular weight is at least about 1500, preferably at least 1800, and not more than about 5000, preferably lower than 2500. In fact, polyesters of too high a molecular weight result in compositions with lower impact strength.

If the composition of the invention comprises a plasticizer, the amount of plasticizer is preferably between 1% and 20%, more preferably between 2% and 10% by weight of the polymer component a.

Optionally, the above composition may further comprise pigments, filler materials, conductive particles, lubricants, mold release agents, heat stabilizers, antistatic agents, extenders, reinforcing agents, organic and/or inorganic pigments (such as TiO) ₂ Carbon black), acid scavengers such as (MgO), flame retardants, smoke suppressants, and the like.

As non-limiting examples of filler materials, mention may be made of mica, alumina, talc, carbon black, glass fibers, carbon fibers, graphite in the form of fibers or powders, carbonates (such as calcium carbonate), macromolecular compounds and the like.

Pigments useful in the composition notably include or will comprise one or more of the following: titanium dioxide, which is Whittaker, clark, from South Plainfield, new Jersey, USA&Available from Daniels corporation; art blue (Artistic blue) #3, topaz blue (Topaz blue) #9, olympic blue (Olympic blue) #190, green bird blue (Kingfisher blue) #211, navy blue (Ensign blue) #214, yellow brown (Russet brown) #24, walnut brown (Walnut brown) #10, golden brown (Golden brown) #19, chocolate brown) #20, iron ore brown (Ironstone brown) #39, honey yellow (Honey yellow) #29, shewand green (shashwood green) 5, and black (Jblack) #1, available from Shellp color company (Shepard Color Company) of Cincinnati, ohio, USA, ohio; black F-2302, blue V-5200, turquoise F-5686, green F-5687, brown F-6109, pale yellow F-6115, chestnut brown V-9186, and yellow V-9404 available from the Feverfew corporation (Ferro Corp.) of Cleveland, ohio, USA, and from the Engelhardy Industrial Co (Englehard Industries) of Edison, new Jersey, USA And (3) pigment.

It is preferred that the total amount of polymer components A, B and C constitute at least 80%, more preferably at least 90%, even more preferably at least 95% by weight of the total amount of polymer contained in the thermoplastic composition of the invention.

Another aspect of the invention relates to a process for making the thermoplastic fluoropolymer composition of the invention described above, comprising mixing polymer components A, B and C optionally with one or more plasticizers and/or other optional ingredients.

Melt compounding may be performed in a continuous or batch apparatus. Such devices are well known to those skilled in the art.

An example of a suitable continuous device for melt compounding the thermoplastic fluoropolymer composition of the invention is notably a screw extruder. In this case, the polymer components A, B and C and other optional ingredients are fed to an extruder and the thermoplastic fluoropolymer composition is extruded. Preferably, the extruder is a twin screw extruder. Examples of suitable extruders which are very suitable for the process of the invention are those obtainable from Werner and Pfleiderer and from Farrel.

This method of operation can also be applied for the manufacture of end products (such as, for example, hollow bodies, tubes, laminates, calendered articles) or for the provision of available granules which contain the desired composition, optionally additives and fillers, in the form of granules in suitable proportions, which facilitate the subsequent conversion into finished articles. From the latter point of view, the thermoplastic fluoropolymer compositions of the present invention are advantageously extruded into strands and these strands are chopped into pellets.

The thermoplastic fluoropolymer compositions of the present invention may be processed according to standard methods for injection molding, extrusion, thermoforming, machining and blow molding.

It is a further object of the present invention to comprise a thermoplastic fluoropolymer composition as described above or an article obtainable by a process as described above.

Advantageously, the article is an injection molded article, an extrusion molded article, a machined article, a coated article or a cast article.

Non-limiting examples of articles are coatings, films, membranes, shaped films, cable jackets, tubes, flexible tubes, hollow bodies, fittings, housings.

Preferably, the article is a tube. The tube according to the invention advantageously comprises at least one layer comprising a thermoplastic fluoropolymer composition.

The articles of the present invention may be advantageously used in the oil and gas industry. Articles for oilfield applications include shock tubes, encapsulated injection tubes, coated sucker rods (coated rods), coated control cables, downhole cables, flexible flowlines (flexible flow line), and risers.

Particular examples of the articles of the present invention are provided by reinforced flexible tubing, notably used in the petroleum industry for transporting recovered fluids between oilfield facilities, and for transporting process liquids between facilities located at the sea surface and facilities located below the sea surface. The reinforced flexible pipe of the present invention typically comprises, preferably consists essentially of, at least one layer comprising the composition of the present invention. It will also be appreciated that the reinforced flexible pipe of the present invention may comprise one or more layers comprising (preferably consisting essentially of) the composition of the present invention.

A common type of such reinforced flexible pipe generally has a tight inner barrier layer comprising the composition of the present invention, on the inside of which is provided a collapse resistant layer (often referred to as a carcass) with the purpose of preventing the inner barrier layer from collapsing due to external pressure impact.

One or more load bearing reinforcement layers are disposed on the exterior of the inner collapse resistant layer and the inner liner. These load bearing reinforcement layers are sometimes also referred to as compressive reinforcement layers, tensile reinforcement layers, or cross reinforcement layers. These layers will be referred to hereinafter as "external enhancement layers". Typically, the outer reinforcing layer consists of two layers on top of each other, wherein the layer closest to the inner liner has properties such that it absorbs radial forces in the tube (pressure reinforcing layer), while the upper reinforcing layer mainly absorbs axial forces in the tube (tension reinforcing layer). Finally, the outer reinforcing layer may be provided with a tight jacket or an outer fluid barrier on its outside, which avoids free exposure of the outer reinforcing layer to the surrounding environment and ensures thermal insulation. In addition, the external fluid barrier may comprise the composition of the present invention.

The articles of the invention are also particularly suited to the CPI market (chemical processing industry), where typically

The corrosion resistant liner comprising the composition of the invention may be applied by powder coating, sheet liner, extrusion liner, rotary liner or other standard techniques;

films comprising the composition of the invention can be manufactured with varying degrees of porosity and manufacturing methods for water purification, food dehydration, filtration of chemicals, etc.;

when excellent temperature and chemical resistance are required, pipes, valves, pumps and fittings comprising the composition as described above can be used in chemical processing equipment. The small pieces can be made entirely economically from the composition of the present invention. Extruded or molded parts include pipes, tubes, hoses, tower packings, pumps, valves, fittings, gaskets, and expansion joints.

The articles of the present invention are advantageously also suitable for architectural and architectonic applications; in this field, typically:

-flexible bellows (flexible corrugated ducts) comprising the composition of the invention advantageously prevents corrosion from SO2 and other combustion products in residential flues;

the pipes and fittings comprising the composition of the invention advantageously provide a long-life hot water supply.

Furthermore, the articles of the present invention may be advantageously used in the semiconductor industry, wherein the compositions of the present invention may be used, for example, as strong, tough, high purity materials that are conventionally used as structural materials in wet bench (wet bench) and wafer processing equipment. In the same field, the composition of the invention is also suitable for the construction of fire-safe wet bench (fire-safe wet benches).

The specific combination of components in the composition of the application combines a VDF polymer matrix enriched in selected VDF homopolymers with the addition of small amounts of selected (per) fluoropolyethers and per (halo) fluoropolymers acting as processing aids, allowing to obtain a polymeric material having excellent mechanical properties and excellent rheological behaviour especially at elevated temperatures (e.g. 150 ℃) such that the composition can be processed under mild temperature conditions and yielding final parts free of cracks or marks or surface defects with excellent surface appearance and good homogeneity and consistency.

The excellent combination of ease of processing and mechanical properties at low and high temperatures makes the compositions and articles of the present application particularly suitable for applications where exposure to high temperatures is required (e.g., as in tubing for oil and gas production).

The disclosure of any patent, patent application, and publication incorporated by reference herein should be given priority if it conflicts with the description of the present application to the extent that the term "does not become clear".

The application will now be described in more detail with reference to the following examples, which are intended to be illustrative only and are not intended to limit the scope of the application.

Examples

DSC

Differential Scanning Calorimetry (DSC) measurements were performed at a heating rate of 10 ℃/min according to ASTM D3418.

MFI: the melt flow index of the test material was measured at 230℃under a piston load of 21.6kg according to ASTM D-1238 standard.

Mechanical properties: tensile tests (modulus of elasticity, yield stress and strain at break) (in MPa) were measured according to ASTM D638 type IV at 23 ℃ and 150 ℃.

Raw materials:

polymer component a: VDF polymers

6015, a VDF homopolymer available from Solvin specialty polymers, inc., having an MFI of 3-4g/10min (230 ℃ C./21.6 kg). />

Polymer 1 is a VDF-HFP copolymer comprising 16% HFP and having an MFI of 3-4g/10min (230 ℃ C./21.6 kg) available from Sorvy specialty polymers Co.

Polymer component B:

fluoropolyether F according to the general formula:

HO-CH2CF2O-(CF2O)q(CF2CF2O)p-CF2CH2-OH

wherein:

table 1: characteristics of the fluoropolyethers used in the examples

Polymer component C:

melt processible perfluoropolymer T:

tetrafluoroethylene (TFE)/perfluoromethyl vinyl ether (PVME) copolymer was prepared as follows:

a 22 liter AISI316 autoclave equipped with a stirrer operating at 500rpm was purged and the following ingredients were introduced:

14.5l of demineralized water-

-127g of a microemulsion formed by:

20% by weightD ₀₂ Which has the formula:

CF ₃ O-(CF ₂ CF(CF ₃ )O) _m (CF ₂ O) _n -CF ₃

wherein m/n=20 and the average molecular weight is 450;

30% by weight of a surfactant having the formula:

Cl-(C ₃ F ₆ O)-(CF ₂ CF(CF ₃ )O) _m1 -(CF(CF ₃ )O) _q -(CF ₂ O) _n1 -CF ₂ COO-NH ₄ ⁺

wherein n1=1.0% m1, q=9.1% m1 and the average molecular weight is 550;

the rest is made of H ₂ O.

The autoclave was placed under vacuum and then heated to a reaction temperature of 75 ℃. Ethane was then fed as chain transfer agent at delta pressure of 2.0 bar, perfluoromethyl vinyl ether (PMVE) was fed at delta pressure of 6.3 bar, and then TFE/PMVE mixture containing 13% MVE by mole was fed to obtain reaction pressure of 21 bar absolute.

Polymerization was initiated by introducing 315ml of Ammonium Persulfate (APS) solution obtained by dissolving 14.5g APS in 1 liter of demineralised water.

The reaction pressure was kept constant by feeding a monomer mixture TFE/PMVE containing 13% by mole of PMVE. After 290 minutes of reaction, the polymerization was terminated, the reactor was cooled to room temperature and the residual pressure was released.

The latex containing 0.329% by weight of solids was drained and combined with HNO ₃ The polymer was then isolated, washed with demineralised water and dried in an oven at 120 ℃ for about 16 hours.

The polymer obtained was at 280℃and 1s ^-1 Has a shear rate of 5Pa×s and T _m2 205.9 ℃ and delta H _2f = 6.279J/g and consists of 13% PMVE on a molar basis and 87% TFE on a molar basis.

And (3) a plasticizer:

DBS: dibutyl sebacate having the formula (C4H 9-OOC- (CH 2) 8-COO-C4H 9).

Example preparation

Example 1:

VDF polymer having a formation ratio of 97/3wt/wt6015 and polymer 1, and is mixed with 0.35wt% of fluoropolyether F, 0.77wt% of perfluoropolymer T and 2wt% of DBS plasticizer (% by weight based on the total weight of VDF polymer). The powders were mixed in a Henschel mixer and pelletized in a twin screw 30-34 extruder (LEISTRITZ) equipped with 6 temperature zones and a 4mm-2 orifice die.

The composition thus obtained in the form of pellets was melted and extruded using a Brabender single screw extruder with a head of size 25x5mm to produce a 2mm thick and 25mm wide tape. The temperature profile and extrusion parameters are reported in the table below.

Table 2: temperature extrusion profile for the manufacture of 2mm thick strips.

Zone 1	℃	190
			Zone 2	℃	200
Zone 3	℃	200
			Zone 4	℃	210
Zone 5	℃	210
			Zone 6	℃	215
Torque moment	Nm	47-49
			Pressure of	Bar of	42-44
Melting temperature	℃	208
			Output rate	Kg/h	1.6
Screw speed	rpm	8

The extruded tape had a smooth surface with no visible cracks and or surface defects.

Example 2:

the same composition and process as in example 1 except that no DBS plasticizer was present and perfluoropolymer T was used at 1.2 wt%.

Example 3:

the same composition and method as in example 2, except that6015 and Polymer 1 was in a ratio of 92/8 wt/wt.

The extruded tape had a smooth surface with no visible cracks or surface defects.

Example 4:

the same composition and method as in example 2, except that only6015 homopolymer (100 wt%) was substituted for the blend. />

Example 5 (comparative):

the same composition and method as in example 2, except that6015 and Polymer 1 was added at a ratio of 80/20wt/wt and 0.36wt% of fluoropolyether F.

Test of examples 1-5:

mechanical properties were evaluated on samples of extruded tape and measured at 23 ℃ and at 150 ℃ according to astm d 638. The data are given in table 3 below:

table 3 mechanical properties of examples 1-5.

The data for examples 1-5 clearly show that samples according to the invention, while having similar values of yield stress and strain at break at 25 ℃ as the reference samples, unexpectedly have much higher values of these properties at 150 ℃. The modulus of elasticity appears generally higher than the reference and comparing example 1 with comparative example 5, it can be noted that, in general, starting from a material having a comparable modulus of elasticity at 25 ℃, the material according to the invention unexpectedly has a higher modulus of elasticity than expected at 150 ℃.

Example 6:

the polymer is6015 was mixed with 0.35wt% fluoropolyether F and 0.77wt% perfluoropolymer T (% by weight based on the total weight of VDF polymer). The powders were mixed in a rotating blender and extruded into pellets as in examples 1-5.

Example 7 (c)

A composition in pellet form as in example 6 was prepared in which no fluoropolyether F was present and the amount was replaced by an equivalent amount of perfluoropolymer T. In the composition, polymer is added 6015 and 1.12wt% perfluoropolymerT (weight percent based on the total weight of VDF polymer).

Test of samples 6 and 7 (comparative):

16g of the pellets of example 6 and example 7c were placed in a micro-compounder Xplore at 230 ℃ for 20 minutes to verify the processability of the two compositions at different rpm. The measured force is an indication of the energy required to melt compound the composition (e.g., when extruding the composition) and is the average of the forces recorded during the last two minutes of the measurement. The data are given in table 4 below:

table 3.

The data in table 4 show that the force drops significantly when the fluoropolyether F is used in combination with the perfluoropolymer T in the composition. The composition according to the invention comprising both one or more (per) fluoropolyethers and one or more per (halo) fluoropolymers also has the advantage of being easier to process using common extrusion conditions.

Claims

1. A thermoplastic polymer composition comprising:

a) A vinylidene fluoride (VDF) -based polymer component A,

2. The composition of claim 1, wherein the total amount of components A, B and C is at least 80% of the total weight of the polymers contained in the composition.

3. The composition of any preceding claim, wherein the polymer component a has a Melt Flow Index (MFI) of less than 20, preferably less than 10, more preferably less than 8g/10min, even more preferably less than 7g/10min, most preferably less than 5g/10min, and at least 0.01, preferably at least 0.05, more preferably at least 0.1g/10min, as measured according to ASTM D-1238 at a piston load of 21.6Kg at 230 ℃.

4. A composition according to any preceding claim wherein the comonomer other than VDF is a fluorinated monomer, preferably selected from vinyl fluoride (VF 1), chlorotrifluoroethylene (CTFE), hexafluoropropylene (HFP), tetrafluoroethylene (TFE), trifluoroethylene (TrFE), (per) fluoroalkylvinyl ether, perfluoroalkyl ethylene, (per) fluorodioxoles or mixtures thereof.

5. A composition according to any preceding claim wherein the (per) fluoropolyether polymer component B consists of one or more (per) fluoropolyethers comprising repeating units selected from the group consisting of:

(I) -CFX-O-, wherein X is-F or-CF ₃ ；

(II)-CF ₂ -CFX-O-, wherein X is-F or-CF ₃ ；

(III)-CF ₂ -CF ₂ -CF ₂ -O-；

(IV)-CF ₂ -CF ₂ -CF ₂ -CF ₂ -O-；

(V)-(CF ₂ ) _j -CFZ-O-, wherein j is an integer selected from 0 and 1, and Z is a fluoropolyoxyalkylene comprising from 1 to 10 repeating units selected from the above classes (I) to (IV)A base chain;

and mixtures thereof.

6. Composition according to claim 5, wherein the (per) fluoropolyether polymer component B comprises and preferably consists of a compound according to formula (I):

T ₁ -(CFX) _p -O-R _f -(CFX) _p’ -T ₂ (I)

wherein:

-each X is independently F or CF ₃ ；

-p and p', equal to or different from each other, are integers from 0 to 3;

(i) -CFXO-, wherein X is F or CF ₃ ，

(ii)-CF ₂ CFXO-wherein X is F or CF ₃ ，

(iii)-CF ₂ CF ₂ CF ₂ O-，

(iv)-CF ₂ CF ₂ CF ₂ CF ₂ O-，

-CFXO-、-CF ₂ CFXO-、-CF ₂ CF ₂ CF ₂ O-、-CF ₂ CF ₂ CF ₂ CF ₂ o-, wherein each X is independently F or CF ₃ The method comprises the steps of carrying out a first treatment on the surface of the And T is ₃ Is C ₁ -C ₃ Perfluoroalkyl groups and mixtures thereof;

-T ₁ and T ₂ Independently selected from

i)H，

ii) a halogen atom, and (ii) a halogen atom,

iii)C ₁ -C ₃₀ a terminal group optionally comprising a heteroatom selected from O, S, N and/or halogen atoms。

7. Composition according to claim 5 or 6, wherein the (per) fluoropolyether polymer component B comprises and preferably consists of a compound selected from:

(b)

HO(CH ₂ CH ₂ O) _n CH ₂ CF ₂ O(CF ₂ O) _n’ (CF ₂ CF ₂ O) _m’ CF ₂ CH ₂ (OCH ₂ CH ₂ ) _n OH, m 'and n' are integers, wherein the ratio m '/n' is in the range between 0.1 and 10, preferably between 0.2 and 5, and n is in the range between 1 and 3;

(c)HCF ₂ O(CF ₂ O) _n’( CF ₂ CF ₂ O) _m’ CF ₂ h, m 'and n' are integers, wherein the ratio m '/n' is in the range between 0.1 and 10, preferably between 0.2 and 5;

8. The composition of claim 7, wherein the (per) fluoropolyether polymer component B comprises and preferably consists of a compound selected from the group consisting of:

(b)

HO(CH ₂ CH ₂ O) _n CH ₂ CF ₂ O(CF ₂ O) _n’ (CF ₂ CF ₂ O) _m’ CF ₂ CH ₂ (OCH ₂ CH ₂ ) _n OH, m 'and n' are integers, wherein the ratio m '/n' is in the range between 0.1 and 10, preferably between 0.2 and 5, and n is in the range between 1 and 3.

9. A composition according to any preceding claim, wherein the weight average molecular weight of the (per) fluoropolyether or polyethers constituting said polymer component B is comprised between 400 and 100000, preferably between 600 and 20000.

10. Composition according to any one of the preceding claims, wherein the polymer component C comprises and preferably consists of one or more per (halo) fluoropolymers selected from TFE copolymers comprising at least 2% wt, preferably at least 7% wt, and at most 30% wt, preferably at most 20% wt, more preferably at most 13% wt of recurring units derived from at least one fluorinated comonomer selected from the group consisting of:

(i) Conforming CF ₂ ＝CFOR _f1’ Wherein R is _f1’ Is C ₁ -C ₆ Perfluoroalkyl groups;

(ii) Conforming CF ₂ ＝CFOX ₀ Perfluoro-oxyalkyl vinyl ether of (1), wherein X ₀ Is C having one or more ether groups ₁ -C ₁₂ A perfluorooxyalkyl group;

(iii)C ₃ -C ₈ perfluoroolefins.

11. The composition of claim 10 wherein the one or more per (halo) fluoropolymers are selected from TFE/PMVE (tetrafluoroethylene/perfluoro) consisting essentially of

-methyl vinyl ether) copolymer:

12. The composition of any preceding claim, wherein the composition further comprises one or more plasticizers, preferably selected from the group consisting of:

dibutyl sebacate (DBS),

-N-butyl sulfonamide,

-acetyl tri-n-butyl citrate,

a polymeric polyester derived from adipic, azelaic or sebacic acid and a diol, having a molecular weight of at least 1500 and not more than 5000,

wherein the plasticizer is preferably present in an amount of between 1% and 20%, more preferably between 2% and 10% by weight of the polymer component a.

13. A process for preparing the thermoplastic polymer composition of claims 1-12, the process comprising the steps of mixing polymer components A, B and C, optionally with one or more plasticizers and/or other optional ingredients, and melt compounding the polymer components A, B and C and optional ingredients in a continuous or batch apparatus.

14. An article comprising the thermoplastic polymer composition of claims 1-12, preferably selected from injection molded articles, extrusion molded articles, machined articles, coated articles, or cast articles.

15. The article of claim 14, wherein the article is selected from the group consisting of a coating, a film, a formed film, a cable jacket, a tube, a flexible tube, a hollow body, a fitting, a housing.